Numerous audio, video, data and control signal sources and sinks are available in television studios. These various types of signal sources include recording appliances, such as tape recorders (MAZ), video servers, cameras and satellite or cable links. The various types of signal sinks once again include recorders, video servers, production mixers. By way of example, different image and audio signal sources are combined with one another to form a program in the production of a news program. A speaker in the studio typically provides the lead through the transmission, which is recorded using one or more cameras. The speaker introduces already recorded programs or direct transmissions. In terms of video, audio and data, these come from a source which is controlled via control signals.
Various signal sources can be connected to their destination by means of switching matrices and mixers. This switching matrix, a so-called crossbar, is a matrix which has a fixed defined number of inputs and a fixed defined number of outputs. Each input can be connected to one specific output which, in detail, means that one input can be connected to a plurality of outputs, but one output can be connected to only one input. A production mixer or presentation schedule mixer, has the same characteristics as a switching matrix, that is able to combine a plurality of signal sources to form one transmission signal. Mixing of different video signals with one another, as well as mixing of different audio signals with one another, are desirable from the composition point of view. For further signal distribution, a presentation schedule mixer is also able to combine audio and video signals into one data stream. Mixing devices use control lines to signal which input signals are passed on and are thus transmission-relevant. Recorders signal that recording is taking place. This signal is known by the expressions “On-Air”, “Red-Light” or tally signaling.
The selection of which signals are produced at which outputs is carried out by an operator in the studio or control room. Connections are generally switched via a plurality of switching matrices and mixing devices, and cover so-called paths. The search for paths, which is assisted by automatic systems, is normally referred to as “pathfinding”. The task of the operator is also made more difficult by paths for different signal types being switched at the same time in the course of production, thus forming a logical unit, a so-called signal bundle. In order to prevent interference with a signal transmission, it is essential to prevent interruption of signal paths and path bundles. The locking of a path, which is assisted by automatic systems, is normally referred to as “path locking”, while the locking of a plurality of paths assisted by automatic systems is referred to as “bundle locking”.
DE 10 2004 009 265.6 discloses a method by means of which the operator can lock or unlock signal paths or signal bundles in the forward or backward direction by means of an appropriate command. By way of example, this prevents a transmission-relevant signal path from being accidentally interrupted. Since locked resources are normally associated with one user, the attempt to unlock an external resource will fail.
In summary, it can be stated that the activity of the operator also has technical aspects, in addition to the creative aspect of mixing and configuring television pictures from different signal sources. On the one hand, the correct signal sources must be selected for the input side, and must be passed to the correct outputs. Even this is quite difficult when there are more than two hundred inputs and two hundred outputs per switching matrix. On the other hand, the locking and unlocking of the input to output connections must be taken into account at the same time in this case, since a plurality of operators work in one studio or control room. For these reasons, the work of the operators in terms of the use of resources which are or are not jointly used is highly demanding.
There is thus a requirement to provide a method which reduces the load on the operator during his work, and as far as possible takes the stated technical aspects away from him, in order that he can concentrate on the creative aspect of his work.